1. Field of the Invention
This invention relates to a cord locking device of synthetic resin for locking a cord to fasten an anorak, a rucksack, a life jacket, a shopping back, etc.
2. Description of the Related Art
This type of prior art cord locking device is exemplified by Japanese Patent Laid-Open Publication No. SHO 54-138799. This cord locking device comprises, as shown in FIG. 6 of the accompanying drawings, a tapering casing A, which opens at opposite ends and has a pair of parallel side walls C at the wide open end, and a slide B adapted to be slidably inserted in the casing A. The casing A has in a front plate there-of a longitudinal aperture D. The slide B has a head portion E, a neck portion F, a ring-shape grip portion G extending from one end of the neck portion F, and a pair of resilient slanting portions H projecting from opposite sides of a base of the neck portion F. The slide B has a saw-toothed surface J on each of opposite side of the head portion E. Each of the slanting portion H also has a saw-toothed surface K on its free end. Further, the slide B has a projection L extending between the head portion E and the neck portion F in such a manner that the projection L is received through the aperture D when the slide B is inserted in the casing A, so that the slide B is slidable within a limited range. As two parts of a cord are inserted through the gaps between the slide B and the respective side walls C of the casing A, the cord is locked by the saw-toothed surfaces J, K of the head portion E and the slanting portions H.
U.S. Pat. No. 4,102,019 also discloses a cord locking device of this kind. In the disclosed cord locking device, a resilient grip portion is bent and inserted in a casing in such a manner that a projection on the grip portion is slidably received in an aperture of the casing. A cord is fastened and locked between engaging projections on outer surfaces of the grip portion and opposite side walls of the casing.
Another cord locking device is known (Japanese Utility Model Publication No. HEI 2-46731) in which a slide is inserted in a casing in such a manner that a resilient guide projecting from the front surface of the slide is received in an aperture of the front plate of the casing, locking a cord between the opposite side walls of the casing and the side surfaces of the slide.
With the first-named known cord locking device, as shown in FIG. 6, when the cord is pulled leftwardly of the casing A, the slide B will be brought toward the narrow open end of the casing A to fasten the cord tightly. Reversely when the cord is pulled rightwardly, it will be difficult to lock the cord by the saw-toothed surface K of the free end of each slanting portion H under the resilience of the slating portions H only, thus simply loosening the cord. Partly since the cord can be fastened in only one way, and partly since the slide B cannot be removed from the casing A after it has once been inserted in the casing A, it is particularly troublesome to exchange the cord with a new one.
In the second-named cord locking device, when the cord is pulled toward the narrow open end of the casing, it will be fastened tightly. When the cord is pulled reversely, it will simply be loosened. Partly since the projection on the grip portion is formed integrally with the grip portion, and partly since the projection is rigid, the grip portion cannot be removed from the casing after the grip portion has once been inserted in the casing. It is therefore yet troublesome to exchange the cord with a new one.
In the case of the third-named cord locking device, since the slide has not a pair of grip portions, the inserting or sliding of the slide with respect to the casing is particularly troublesome.